Portable computing devices such as personal digital assistants (PDAs), including Palm Pilots, Handspring Visors, hand-held PCs, and similar devices, have become incredibly popular because of their functionality and flexibility. For purposes of this application, the term computing device should be understood to include all computing devices, including those with additional functionality, including: desk-top, laptop, hand-held, palm top and wearable computers; and also cellular phones, telephones, two-way paging devices, radios, communicators, calculators, organizers, e-books, navigation devices, automobile electronics, digital interactive television controllers, and other electronic devices having computing capability. However, for ease of description, this application will focus on portable computing devices such as the Palm Pilot family of hand-held devices (Palm Inc., Santa Clara, Calif.) and the Handspring Visor (Handspring, Mountain View, Calif.).
These personal digital assistants (or PDAs) include buttons and touch sensitive screens allowing input of data in a variety of ways, including various forms of handwriting recognition and simplified keyboards. For some persons and applications, these forms of data input are insufficient. For example, a person who wishes to input information, such as recording what meals were eaten during a day or expenses incurred on a trip, must grasp an input stylus with one hand while holding the PDA in the other hand. The stylus is then used to touch the touch sensitive screen in a manner indicative of the input desired. This obviously ties up both of the person's hands, and requires a moderate level of visual and mental focus. It would be more desirable if data input could be made using a person's voice, rather than manual manipulation.
A partial solution is offered by some hand-helds which include voice recording capability. A person who wishes to quickly record information on the PDA presses a record button and speaks into a microphone. Later, the recorded information may be played back. Unfortunately, this approach falls far short of what is desirable. The voice recording is only voice-to-voice and therefore someone must later listen to the recorded voice and manually input the data. While the original recording step may be easier than manual manipulation, manual manipulation is not avoided because it must be completed at a later time. More desirable would be a voice-to-text voice recognition capability so that a person may speak commands and information and the PDA responds to the commands and records the information in text form. However, voice-to-text speech recognition is extremely complex and requires powerful computer processors and a large data storage capability. Current PDAs offer only a fraction of the necessary processing power and storage.
Speech recognition software and systems are well known in the art, for example as described in U.S. Pat. Nos. 5,749,072 to Mazurkiewicz et al., and 6,167,255 to Kennedy III et al, incorporated herein by reference.